body {
    font-family: 'Source Sans 3', sans-serif;
    margin: 0;
    padding: 0;
    background-size: cover;
    background-position: center;
    color: #fff;
}

#header {
    background: 
        linear-gradient(to left, rgba(255, 165, 0, 0.6), rgba(255, 165, 0, 0.2), rgba(255, 165, 0, 0)),
        url('fond_floute.png') no-repeat center center;
    background-size: cover;
    color: #ffffff;
    margin: 0;
    padding: 1em;
    text-align: center;
    position: relative;
}

#header h1 {
    position: relative;
    z-index: 2;
    font-size: 50px;
    font-family: 'Oswald', sans-serif;
}

#header::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: 1;
}

.nav-button {
    display: inline-block;
    padding: 10px 20px;
    margin: 0 10px;
    background-color: #f0f0f0;
    text-decoration: none;
    color: black;
    font-weight: bold;
    border-radius: 5px;
    font-family: 'Oswald', sans-serif;
    position: relative;
    z-index: 2;
}

.nav-button:hover {
    background-color: #ddd;
}

.container {
    display: flex;
    justify-content: flex-start;
    align-items: flex-start;
    max-width: 1200px;
    margin: 20px auto;
    padding: 20px;
}
.bilan-container {
    background-color: white; 
    color: black;
    font-family: 'Oswald', sans-serif;
    padding: 50px;
    width: 60%;
    max-width: 800px;
    border-radius: 15px;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.3); 
    text-align: center;
    

    margin: 100px auto; 
    position: relative; 
}